Minimally invasive medical procedures are performed in various passageways in the body using elongated instruments inserted through natural orifices or small surgical openings. In some procedures, it is desirable to provide treatment of some diseases using en bloc tissue removal through an elongate device, for example removing tissue lesions or polyps.
In some procedures, such as endoscopic submucosal dissection (ESD), a solution may be submucosally injected between layers of tissue to create a tissue elevation and then electrocautery may be used to cut the margins of the elevated tissue to remove the diseased tissue. Electrocautery devices, such as needle knives, that are currently available all operate in a monopolar fashion through the accessory channel of the endoscope.
One complication associated with the use of monopolar needle knives to excise the tissue is that the tissue may be completely perforated by the electrocautery device rather than excising only specific layers. Currently, advances have been made in limiting the perforations by limiting the use of electrocautery devices to those practitioners with advanced endoscopic skills. Additionally, some devices have been made that include an insulated distal tip to limit the perforations caused by electrocautery devices.
There is a need for an apparatus and a method to provide an electrocautery device that reduces the risk of complications, such as perforations, and allows for cutting of specific layers of tissue. In addition, an electrocautery device that allows for an open accessory channel on an endoscope is advantageous.